Terminal blocks are typically used in the telecommunications industry to connect multiple wire pairs, for example, to connect telephone service wires to telephone company distribution cables. Such terminal blocks typically connect from 2 to 50 individual service wire pairs to the distribution cable that may have several thousand-wire pairs. Generally, the terminal block is spliced to the distribution cable through a splicing cable or stub cable that forms part of the terminal block. The customer service wires are then connected to the terminal blocks through some type of terminal, which, ideally, enables the service wires to be easily connected, disconnected and reconnected on site.
In the telecommunications industry, a large number of wires connect the various component of the system through the terminal block. To organize the many wires, some telecommunications operators use color-coding on the wire jackets based on signal type, and channel number or program content.
Typically, telephone-wiring applications use a uniform scheme for dealing with a large number of wires for the telephone industry. The scheme uses two color codes—one for large numbers of wires organized in pairs and the other for smaller numbers of wires that also can be organized in pairs. For large number of wires, each pair is assigned a two-color code. The colors are selected from two groups of five, resulting in what is called a binder-group of 25 pairs. The colors used for a group are white, red, black, yellow and violet. The colors used for “pairs within a group” are blue, orange, green, brown and slate. Each pair must have a unique color combination. One wire within each pair has a solid background of its group color and stripes of the “pair within the group” color; the second wire has the colors reversed. Cables with more than 25 pairs of wires are constructed from 25-pair groups.
For small wiring groups, such as wires for an individual telephone station or terminal, a second color-code scheme can be used. The alternate color uses the first three pairs of the standard color code (white-blue, blue-white, and so on) or alternatively can use the six alternate color wires.
Originally, telecommunications terminals were optimized for use with copper drop wires. Through an evolutionary process, a plurality of different wire sizes and kinds of wire have been employed to connect the subscriber to the phone company. The gauges can vary from 18½ to 26 AWG (American Wire Gauge) gauge copper based wires some of which may have steel cores. Most common copper wires are between about 19-24 AWG gauge.
Traditionally, standard conventional terminals had an electrical connector secured in a suitable dielectric base material. The wires are stripped of their insulation, formed in a “C” shape, and connected to the electrical connector. After connecting the wires to the electrical connectors, a potting material is poured by hand over the electrical connectors and electrical wires.
The potting by hand of an electrical terminal block is typically performed by mixing a liquid potting compound or gel. The liquid potting compound is applied over the connection between the electrical contacts and the electrical wires, which forms the electrical circuit. The gel cures and solidifies the components into a solid mass, which protects the electrical circuit from moisture, dust, contaminants, vibrations and impact damage. The potting process provides environmental and mechanical protection for the connections in the terminal blocks. The process, however, is craft sensitive and time consuming.
Alternatively, the terminal block can be manufactured using insulation displacement contacts (IDC) or terminals, which cut through the wire insulation without requiring wire stripping. Although, the IDC partially addresses the time consuming installation problems, the process is still not only labor intensive but is also very time consuming. In addition, the IDC terminals require hand installation of the individual termination of the copper wires within the cable to the back of the terminal by hand and thereafter potting by hand.
Accordingly, there is a need for improvements including increased efficiency and increased flexibility over the hand-made products made by labor intensive manufacturing processes that can be used for the production of an overmolded terminal block for telecommunication cables, which eliminates the wrapping of wires by hand around the electrical connectors, and the hand poured gravity potting process. In addition, it would be desirable to have a method and process for manufacturing an overmolded terminal block, which allows for the use of dielectric materials that cannot be used with traditional potting compounds used in the hand poured gravity potting process.